Filter.



C. BUTTERS.

FILTER.

APPLICATION FILED OCT. 22. 1913,

EJ55 068. Patented Dec. 21, 1915.

3 SHEETSSHEET l- WITNESSES INVENTOR MZanr I Lia/11w ficawm I I MANOR H8,

0. BUTTERS.

FILTER.

.APPLICATION FILED OCT. 22. 1913.

Patented Dec; 21, 1915.

3 SHEETS-SHEET 2.

llvi/i 11/70/23 I v l WITNESSES semi-solid material from the filter. j

UNITED sran CHARLES BUTTERS, or OAKLAND, CALIFORNIA.

. FILTER.

' Specification of Letters Patent. Patgnted DQQ 21, 1915 original'application filed iTul y s, 1913, Serial No. 774,294. Divided and this application filed October 22,

' 1913. Serial No.-796,594.

To all whom it may concern 4 Be it known that I, CHARLES Burrnus, a

citizen of the United States,iand a resident v of Oakland, county of Alameda, State of California, have invented certain new and useful Improvements in F ilters, of which the following is a specification. i

The invention relates. .to the filtration of liquids from liquids carrying solidand semisolid material, and to a filterfor performing the filtering operation.

The object of the invent on is to provide an improved apparatus to be used .in a process of separating fluid fromsohd and-semisolid material and of removing. the solid and.

Another object of the invention is to provide a filter in which the filtering operation takes place in a substantially horizontal plane, and the discharge or removal of the solids and semi-solids takes place in a plane at amangle to the horizontal.

A further object/of the invention is to provide an apparatus in which the filtered liquid may be withdrawn from a stream of material to be filtered.

The invention possesses many other objects and advantageous features which with the foregoing, will be set forth at length in the following description where I shall outline.- in full that form of the invention which I have selected for illustration in the accompanying drawings. The novelty of the. invention will be included v in the claims succeeding said description. From this it will be apparent that I do not limit myself to the showing made by said drawings and description, as I may adopt many variations within the scope ofmy invention as expressed in said claims.

The present invention is adapted to metallurgical operations, particularly to the filtration of slimes in the cyanid process, al-

though it may be employed in any instance where it is desirable-gto separate the solid or semi-solid material"from its carrying liquid. In the filtering operation, the liquid is drawn or passed through a filtering me-- dium, causing the solids and semi-solids to be deposited in the form of a cake on the filter-- ing medium. According to my invention, I form the cake in a substantially horizontal plane and-may do so from a flowing stream of slime or pulp, and I discharge the cake by tipping the filter to an inclined or vertical The cake is formed on the filter medunrr;

from a shallow bath .of slime or pulp which may be afiowing stream, and such forming may be continuous until a cake of the desired thickness is obtained. After the cake has been .formed, it may be treated with a .shallow bath or with a flowing stream of barren. solution, and of strong solution or otherwise, and it may be washed or impoverished by a shallowbath or by allowing ciently dried and discharged or removed.

qlheliquid to be filtered is drawn through the filtering medium by means of a vacuum or lowering of pressure on the side of the medium removed from the cake, and the process of filtering and further dissolving and impoverishing is continuous and is ac complished without intermitting the vacuum and without undue drying of the cake which might cause cracking of the cake.

In the accompanying drawings I have shown one form of apparatus for carrying out the method of my invention, but it is to be understood that the method is not limited to any particular form of apparatus. These drawings show a filter composed of a plurality of filter units arranged in superposed relation, but it is to be understood that one or any number of filter units may be .employed and that the various units, in a. multiunit installation, may be arranged in any desired relation with respect to each. other.

Referring to said drawings: Figure 1 is a rear end view of one form of filter. Fig.

2 is a side view of the filter shown in Fig. 1. Fig. 3 1s a crosssect1on of one of the filter units, part thereof being broken away stream of wash water, after which it is suiF- such as angle irons 17, The frame is pro- Aided with trunnions 4, engaging in bearings 5 arranged on. the pedestals (i so that the frame may be. turned through an angle. The turning of the frame may be accomplished by any suitable means 7, such as a hand wheel or motor, through the medium of the worm gear 8 and the sprocket 9, chain ll), sprocket 1l, pinion 12 and gear segment 12-5 secured to one of the trunnions l. \Vhen the cake is being formed or treated, theliltcr units lie in a substantially horizontal plane i in the eye r vided with an overflow lip or side 15 which is preferably shaped, as shown,in order to facilitate the discharge that end is depressed, ==The units are held from falling out of the frame when it is tilted by the angle pieces 16 which are placed along the inside front the angle pieces 17. They have no tendency to fall out from the rear for the reason that the frame is never tilted in that direction. This allows ready removal of the units when the frame is tilted byinserting hooks or other suitable means bolts 18 fastened in the rearof the units.

Secured in the bottom of the pan is the filter leaf which is composed of two pieces 19-420 of canvas or other suitable material. between which, at suitable intervals, are arranged the grooved or corrugated cross fillers 21. These fillers, besides holding the two pieces of canvas apart, serve also to help support the weight of the cake and liquid, and to prevent the bottom of the pan from sagging and bellying. These fillers extend transversely of the pan and are held in place by stitching the two pieces of canvas together between adjacent fillers. The sides and the rear end of the canvas are prefer ably clamped together and to .the corresponding sides and end of the pan by means of the angles 22 and lheclamps 23 and bolts 24:. There are two of the angles 22. One extends from the the other side to the front end. They are, therefor j bent around the rear corners so as to hold the c: nvas all around on two sides and one end. The front end of the canvas is held by the member 25 and around on the pan are two pipes or an inclined or.

of the cake when accumulating in end of the frai'nef The units are placed. in the frame from the. rear and rest on front end to the middle of the rear end, and the other from that point 1 the bolts 26. Themembei 46 placed under the pan to add strength to the front end The heads of the bolts are countersunk seas to make as'little roughening ofthe lower.

surface as possible, viates the necessity of punching or cutting holes in the canvas and renders the replacement of the canvas simple, should its removal be necessary or desirable. A ranged between the two pieces of the canvas and preferably lying adjacent the two sides of conductors 27 provided with a plurality of perforations 2-8.

These pipes 27 project from the pan at some suitable place so that one or both may readily be connected to a pipe or conductor'29, thereby placing the space of canvas in communication with the conductor 29. It is desirable to occasionally wash out the inside of thedeaf and forthis purpose one of the pipes 21 may be opened to atmosphere at this time, and the other remain connected, as shown. When. it is desired to wash out the leaf water is'adinitted through the one of the pipes 27. the leaf andb discharged through the other pipe 27. In order. to' prevent water from the bottom.

washing out of the lower piece of canvas material.

leaf, I- prefer to coatthe 20, with a waterproof This construction ob pipes 39, 31, 30 and29 and T hiswill flow through of the pan 'be-. low the filter leafduringcake discharge and between the pieces The slime or pulp to be filtered is fed onto the filter leaf, preferably at the rearfcorner, through the nozzles or conductors are preferably 32, which so arranged that the feeding I stream isdirected vigorously along one of .5

the longer sides of the pan and surface of the bath. 1 have found'f-that this arrangement produces an energetic movement of circulation and thereby a substantially uniform distribution of sands and slime and results ina substantially uniform cake. The nozzles or feed; pipes are preferahly connected to a manifold pipe 83 whiclrmay be placed in communication with the supply of slime to be filteredQ The pipe 33' is mounted on one side of the tilting frame and is provided with a joint so that it may be detached from the pipe 35 andbe tilted with the frame. The pipe 33 is mounted to one side, as shown in Fig. 1, so that the units may be readilyplaced in the frame. This'can be done because thefeed pipes 32 normally go into the units over the of the shallow bath,

below the p referably' g top' thereof, and, therefore, the units may he slid in'place underneath the pipes 32 onto the angle supports.

The liquid to be filtered is drawn through the filtering medium 1 9by a vacuumor uced thereunder,

one or both of the pipes tial. vacuum' prod drawn off through and 1S.

pipe 29 is provided with a quick detachable coupling 45 connecting the pipe to a flexible conductor 30. The pipe 29 is attached to the tilting frame and before tilting maybe detached from the flexible conductor. ThefieXible-conductor 30 is connected to the conductor 31 to which are connected the valve controlledconductors 38-39 which are connected respectively to the vacuum pump 4L0 and to a source of air and water under pressure, not shown. In operation I prefer to feed theu'nate'rial to be filtered onto the leaves in excess of their filtering capacity, and this means that there will be an overflow at the end opposite the feed. It is desirable that this overflow be saved so I have provided a launder 41 which catches the overflow and conducts it to a, tank 42. Connected with the upper end of'this tank 42 is a pipe 43 leading to the main stock pulp I tank 44. A float valve, or other suitable means-4C7, is arranged to regulatethe amount of pulp in the tank 42. Connected to the tank 42 is a pump 48 which is'adapted to force the pulp up the pipe '33 into the filtering units. It will be seen, .therefore, that all the overflow is refed to the units and any further amount necessary to supply the units is automatically taken from the main stock. All the above apparatus makes it possible to handle very little more pulp than is necessarv.

For the purposes of simplicity and clarity I. shall describe the filtering operation as carried on in one filter unit, it being understood. that the same operation takes place in all of .the units of theifilter. With the filter in a horizontal or a substantiallyhorizontal position, the stream of slime or pulp is fed into the pan, and a vacuum or partial vacuum is produced below the-filtering me dium by placing the vacuum pump in communication with the conductor 29. The slime circulates over the entire surface of the filtering medium and forms a shallow bathabove it and seals the vacuum. Thereupgn the suction draws the solid particles downward upon the/filtering medium and draws the liquid through the filtering medium. During the formation of the-cake the frame may be tilted slightly to any desired angle to control the building up of the cakes, or the amount and character of the overflow of the bath, if any. The feed of the slime may be so regulated in proportion to the rate of withdrawal of the filtered liquid by the suction that the feed will be continuous, without discharging any of the bath over the discharge end of the pan. On the'other hand,

oi. preferably, the feed of the slimes may be many desired excess of the rate at which the.

liquid is withdrawn by the suction so that there is an overflow from the discharge end of the pans, By this latter method a continuous stream of slimes may be fed into the pans and kept in vigorous circulation over the filtering medium or over the cake thereon, and clear liquor drawn by the suction through the cake and filtering medium and also a continuous stream of slimes discharged over the overflow lip of the pans until the thickness of the cake reaches the economical limit. The feed of slime is then stopped and liquor of the bath is drawn through or into the cake and filtering medium. Thereupon without intermitting the suction barren solution is fed through pipes 32 into the pans and onto the filter cake. until the pans .are full and overflowir, and the suction draws the barren solution through the cake and filter medium as long as desired, mechanically displacing the dissolved gold from the cake and chemically dissolving and displacing some of the undissolved'gold. At

the end the bath is sucked nearly dry as before.

l/Vash water in any quantity desired maythen be fed through pipes 32into the pans on top of the cakes without intermitting the suction the'water being allowed to overflow and the cakes thereby impoverished of their contained solutions and dissolved values if any. After the feed of wash water is discontinued, the suction is-maintained to draw through the last of the shallow bath.

of wash water and to dry the cake.- When the cake is sufficiently dry, the suction is discontinued by closing the valvein conductor 38. The valve. in conductor 39 is then opened, and water is admitted below the filtering medium through the pipe 27 for the purpose of wetting the medium, and

thereby loosening the cake. The filter frame is then tilted until the filter pans are in .an inclined or vertical position whereupon the cakes slide off into any suitable receptacle and are sluiced away or otherwise removed. I have found it desirable in factor in the discharge of the cakes, however, is the tilting of the filtering media to a substantially vertical position, whereby the cakes are loosenedfrom the. media and sweep themselves off by their oWn accumulating weight. If desired the tilted -pans with their filtering media may be hosed or sprayed for further cleansing.

is returned to the horizontal, or substan- After the cake has been discharged the filter frame the suction continued until nearly all the tially horizontal, position, and is in condi-.-

tion for another cycle of operations.

The matter claimed in this application 'is divided out of my application, Serial No. 774,294, filed July 18, 1913, in which the claims are directed to the process. 1

Having described my invention what I claim as new and desire to secure by Letters Patent is l. A filter comprising an open frame, a

plurality of superposed filter media in shal low pans carried by said frame and adapted to be-tilted from a horizontal. to an 111- ehned position.

21A filter eomprising an open frame adapted to be tilted, a plurality of superposed filter media arranged on saidframe, and means for tilting said frame.

3. A filter comprising a substantially horizontal filtering medimn arranged in a shallow pan and adapted to be tilted, means for feeding excess of the material to be filtered onto said medium, and means for drawing a liquid portion thereof through said medium.

4:. An open filter comprising a plurality of superposed filter media, means for tilting said media about a horizontalaxis, means for simultammusly lowing a stream of slime onto each of said media, and means for simultaneously withdrawing a liquid' 1" arranged near the bottonrof each pan,

means for feeding the material to be fil tered onto said filter medium, means for supporting said medium free of the bottom of the pan, and means for drawing liquid through said medium.

7. A filter comprising a plurality of horizontally arranged superposed shallow pans,

a filter medimnarranged in each of said pans, a plurality of cross fillers in each pan below said filter medium, means for feeding the material to be filtered. to each pan, and means for drawing liquid through said me dium.

8. In a horizontal filterthe combination of an open frame having a plurality of shallow filter elements therein, means for supplying material. to be filtered to. said elements whereby cakes are formed therein, and means for tilting said elements to discharge the cakesv 7 9. In a filter the combination of a plurality of substantially horizontal shallow filter elements, means for simultaneously supplying to said elements material to be filtered or drawn. through, means for simultaneously carrying away the filtered liquid fronrsaid elements, means for carrying awavthe overllow from said elements, and means for tilting said elements. i

10. in a filter plant a plurality of individual means for filtering, means for, supplying material to be filtered from a tank to said filter means in excess of their filtering rapacity and means for returning the excess to the tank whereby it may be again supplied to said filtering means.

11. A filter comprising an open tiltable frame, a plurality of shallow-pans place CHARLES BUTTERS.

\Vitnesses:

NEWT N A. Bnnenss,

1 lunwlN brie-ER.

(1 8O :in'said frame. and having filtering means 

